Summary: A growing interest in gas sensors necessitates the requirement for a test system that is reliable and capable of handling multiple gas analytes at various concentrations. Most test systems currently used do not incorporate some type of standard with which to verify the actual concentrations of the gas analytes being tested, but rather calculate concentrations indirectly. The problem is that the calculated concentrations rarely take into account any loss that may occur across the test system. The test system described herein uses a specialized gas chromatograph (GC) that is capable of detecting down to the ppb range. It can either be used to screen potential sensing materials or to verify the actual concentration being tested for a specific sensor.